This document discusses communication and collaboration models. It begins by explaining that human communication involves non-verbal cues like eye contact and gestures that provide context. Text-based communication reduces these cues. It then examines models of face-to-face communication, noting how eye contact, gestures, turn-taking, and back channels are used. Models of text-based communication are also discussed, noting how it has weaker grounding constraints and context due to reduced feedback. The document concludes by stating that group work is more complex as it is influenced by social relationships and environment.